Retaining mechanisms for trocar assemblies

ABSTRACT

Adapter assemblies include a trocar assembly releasably securable within an elongate body by a retaining mechanism. The retaining mechanism includes a housing, and first and second flexible arms extending from the housing. The first and second flexible arms each include a free end, and a locking portion disposed on the free end. The locking portions of the first and second flexible arms are positioned to be received within first and second cutouts of a trocar housing of the trocar assembly when the trocar assembly is received within the distal portion of the elongate body and in a first rotational orientation relative to the longitudinal axis, and the locking portions of the first and second flexible arms are flexed radially outward from the respective first and second cutouts when the trocar assembly is in a second rotational orientation relative to the longitudinal axis.

FIELD

The disclosure relates to reusable adapter assemblies for surgical stapling devices. More particularly, the disclosure relates to a retaining mechanism for releasably securing a removable trocar assembly within a reusable adapter assembly.

BACKGROUND

Surgical devices for applying staples, clips, or other fasteners to tissue are well known. Typically, endoscopic stapling devices include an actuation unit, e.g., a handle assembly for actuating the device and a shaft for endoscopic access, and a tool assembly disposed at a distal end of the shaft. In certain of these devices, the shaft includes an adapter assembly, having a proximal end securable to the handle assembly and a distal end securable to the tool assembly.

Circular stapling devices typically include a trocar assembly for supporting an attached anvil assembly. The trocar assembly may be releasably securable within the adapter assembly to permit cleaning, sterilization, and reuse of the adapter assembly. It would be beneficial to have a retaining mechanism for releasably securing the trocar assembly with the adapter assembly.

SUMMARY

Adapter assemblies for connecting loading units to handle assemblies include a sleeve, a trocar assembly releasably securable with the sleeve, and a retaining mechanism configured to releasably secure the trocar assembly within the sleeve and to facilitate cleaning and sterilizing of the adapter assembly.

An adapter assembly for connecting a loading unit to a handle assembly includes an elongate body having a proximal portion and a distal portion and a retaining mechanism configured to releasably secure the trocar assembly within the distal portion of the elongate body. The proximal portion of the elongate body is configured for operable engagement with an actuation assembly and the distal portion defines a longitudinal axis and is configured to operably receive a trocar assembly. The retaining mechanism includes a housing, and first and second flexible arms extending from the housing. The first and second flexible arms each include a free end, and a locking portion disposed on the free end. The locking portions of the first and second flexible arms are positioned to be received within first and second cutouts of a trocar housing of the trocar assembly when the trocar assembly is received within the distal portion of the elongate body and in a first rotational orientation relative to the longitudinal axis, and the locking portions of the first and second flexible arms are flexed radially outward from the respective first and second cutouts when the trocar assembly is in a second rotational orientation relative to the longitudinal axis.

In some aspects of the disclosure, the first and second flexible arms are in a locked position when the trocar assembly is received within the distal portion of the elongate body in the first rotational orientation relative to the longitudinal axis, and the first and second flexible arms are in a release position when the trocar assembly is received within the distal portion of the elongate body in the second rotational orientation relative to the longitudinal axis. Rotation of the trocar housing of the trocar assembly about the longitudinal axis from the first rotational orientation to the second rotational orientation may flex the first and second flexible arms radially outward. The trocar housing of the trocar assembly may be rotated in a first direction about the longitudinal axis from the first rotational orientation to the second rotational orientation. The first direction may be counterclockwise about the longitudinal axis.

In certain aspects of the disclosure, the lock portion of the first flexible arm is disposed opposite the lock portion of the second flexible arm. The housing may define a longitudinal passage for receiving the trocar housing of the trocar assembly. The adapter assembly may further include a trocar assembly releasably securable within the distal portion of the elongate body, the trocar assembly including a trocar housing defining first and second cutouts. The trocar housing may include first and second camming surfaces defining the respective first and second cutouts. The first and second camming surfaces may be configured to flex the respective first and second flexible arms radially outward when the trocar assembly is rotated about the longitudinal axis from the first rotational orientation relative to the longitudinal axis to the second rotational orientation relative to the longitudinal axis. The housing and the first and second flexible arms may be integrally formed.

A surgical stapling device includes an actuation assembly, an adapter assembly including an elongate body having a proximal portion and a distal portion, a trocar assembly releasably securable within the distal portion of the adapter assembly, and a retaining mechanism configured to releasably secure the trocar assembly within the distal portion of the elongate body. The proximal portion of the elongate body is in operable engagement with the actuation assembly. The trocar assembly includes a trocar housing defining first and second cutouts. The retaining mechanism includes a housing, and first and second flexible arms extending from the housing. The first and second flexible arms each include a free end, and a locking portion disposed on the free end. The locking portions of the first and second flexible arms are positioned to be received within the respective first and second cutouts in the trocar housing of the trocar assembly when the trocar assembly is received within the distal portion of the elongate body in a first rotational orientation relative to the longitudinal axis, and the locking portions of the first and second flexible arms are flexed radially outward from the respective first and second cutouts when the trocar assembly is received within the distal portion of the elongate body in a second rotational orientation relative to the longitudinal axis.

In some aspects of the disclosure, the first and second flexible arms are in a locked position when the trocar assembly is received within the distal portion of the elongate body in the first rotational orientation relative to the longitudinal axis, and the first and second flexible arms are in a release position when the trocar assembly is received within the distal portion of the elongate body in the second rotational orientation relative to the longitudinal axis. Rotation of the trocar housing of the trocar assembly about the longitudinal axis from the first rotational orientation to the second rotational orientation may flex the first and second flexible arms radially outward. The trocar housing of the trocar assembly may be rotated in a first direction about the longitudinal axis from the first rotational orientation to the second rotational orientation. The first direction is counterclockwise about the longitudinal axis. The lock portion of the first flexible arm may be disposed opposite the lock portion of the second flexible arm. The housing may define a longitudinal passage for receiving the trocar housing of the trocar assembly.

In an exemplary aspect of the disclosure, the retaining mechanism includes first and second retention members. The first and second retention members are movable between a locked position in which the first and second retention members are received within the respective first and second openings in the trocar housing and a release position in which the first and second retention members are spaced from the respective first and second retention members. Each of the first and second retention members includes a first camming surface configured to engage a proximal end of the trocar housing as the trocar assembly is received within the outer sleeve to move the first and second retention members to the release position, and a second camming surface configured to engage the trocar housing when the trocar assembly is rotated about a longitudinal axis within the outer sleeve to move the first and second retention members to the release position.

In another exemplary aspect of the disclosure, the retaining mechanism includes a housing and an insert member. The housing defines a longitudinal opening for receipt of the trocar assembly and a slot in communication with the longitudinal opening for receipt of the insert member. The insert member defines an opening for receipt of the trocar assembly and including first, second, and third flat sections, corresponding to the first, second, and third flat sections of the trocar housing, wherein the first, second, and third flat sections of the trocar housing align with the first, second, and third flat sections of the insert member when the trocar assembly is in a first rotational orientation, and the first, second, and third flat sections of the trocar housing are misaligned with the first, second, and third flat sections of the insert member when the trocar assembly is in a second rotational orientation.

In yet another exemplary aspect of the disclosure, the retaining mechanism includes a housing, and first and second flexible arms extending from the housing. The first and second flexible arms each including a free end and a locking portion disposed on the free end. The locking portions of the first and second flexible arms are receivable within the first and second cutouts. The trocar assembly is rotatable within the outer sleeve from a first rotational orientation in which the locking portions of the first and second arms are received within the respective first and second cutouts to a second rotational orientation in which the locking portions of the first and second arms are spaced from the respective first and second cutouts.

In still another exemplary aspect of the disclosure, the retaining mechanism includes first and second retention members. The first and second retention members are movable between a locked position in which the first and second retention members are received within respective first and second cutouts in the trocar housing and a release position in which the first and second retention members are spaced from the respective first and second retention members. Each of the first and second retention members includes a first camming surface configured to engage a proximal end of the trocar housing as the trocar assembly is received within the outer sleeve to move the first and second retention members to the release position. The first and second cam surfaces of the trocar housing engage the respective first and second retention members as the trocar assembly is rotated within the outer sleeve about the longitudinal axis to move the first and second retention members to the release position.

In still yet another exemplary aspect of the disclosure, the retaining mechanism includes first and second retention members. The first and second retention members are pivotable between a locked position in which the first and second retention members are received within the respective first and second openings in the trocar housing and a release position in which the first and second retention members are spaced from the respective first and second openings in the trocar housing. Engagement of the first and second retention members with the seal member when in the locked position frictionally retains the first and second retention members in the locked position.

In another exemplary aspect of the disclosure, the retaining mechanism includes a cam wire moveable between first and second positions, a button member for moving the cam wire between the first and second positions, and first and second retention members movable between a locked position when the cam wire is in the first position and a release position when the cam wire is in the second position. The button member includes a flange engageable with the stop feature of the drive member when the drive member is in the first longitudinal position and the flange is spaced from the stop feature when the drive member is in the second longitudinal position.

In still another exemplary aspect of the disclosure, the retaining mechanism includes first and second retention members. The first and second retention members are pivotable between a locked position in which the first and second retention members are received within the respective first and second openings in the trocar housing and a release position in which the first and second retention members are spaced from the respective first and second openings. Engagement of the first and second retention members with the seal member when in the locked position frictionally retains the first and second retention members in the locked position. Longitudinal movement of the trocar assembly in a first longitudinal direction when the first and second retention members are in the locked position moves the first and second retention members to the release position.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and, together with a general description of the disclosure given above, and the detailed description of the embodiments given below, serve to explain the principles of the disclosure, wherein:

FIG. 1 is a perspective view of a surgical stapling device including a handle assembly and an adapter assembly according to an exemplary embodiment of the disclosure;

FIG. 2 is a perspective view of the adapter assembly shown in FIG. 1 with a trocar assembly extending from a distal portion of the adapter assembly;

FIG. 3 is a perspective view of the distal end of the adapter assembly and the trocar assembly shown in FIG. 2, with the trocar assembly separated from the adapter assembly;

FIG. 4 is a side perspective view of the distal portion of the adapter assembly with an outer sleeve removed to expose a retaining mechanism;

FIG. 5 is a side perspective view of the retaining mechanism shown in FIG. 4, with components separated;

FIG. 6 is a side perspective view of a retention member of the retaining mechanism shown in FIGS. 4 and 5;

FIG. 7 is a side perspective view of the retention member shown in FIG. 6, rotated about a longitudinal axis one-hundred eighty degrees (180°);

FIG. 8 is a cross-sectional side view the retention member shown in FIGS. 6 and 7, taken along section line 8-8 shown in FIG. 6;

FIG. 9 is a cross-sectional top view of the retention member shown in FIGS. 6-8, taken along section line 9-9 shown in FIG. 6;

FIG. 10 is side perspective view of the retaining mechanism shown in FIGS. 4 and 5, in a first or locked position;

FIG. 11 is a cross-sectional side view taken along section line 11-11 shown in FIG. 10;

FIG. 12 is a cross-sectional top view of the trocar assembly shown in FIGS. 2 and 3, taken along section line 12-12 shown in FIG. 3;

FIG. 13 is a cross-sectional top view of the adapter assembly shown in FIGS. 1-3, taken along section line 13-13 shown in FIG. 3;

FIG. 14 is a cross-sectional side view of the adapter assembly shown in FIGS. 1-3, including the trocar assembly shown in FIGS. 2 and 3 partially received within the adapter assembly;

FIG. 15 is the cross-sectional side view of the adapter assembly and trocar assembly shown in FIG. 14, with trocar assembly fully received within the adapter assembly;

FIG. 16 is a cross-sectional end view of the adapter assembly shown in FIG. 15, taken along section line 16-16 shown in FIG. 15, with the trocar assembly fully received within the adapter assembly;

FIG. 17 is the cross-sectional end view of the adapter assembly and trocar assembly shown in FIG. 16, with the trocar assembly in a rotated position;

FIG. 18 is a side perspective view of an adapter assembly according to another exemplary embodiment of the disclosure, including a trocar assembly secured within the adapter assembly by a retaining mechanism;

FIG. 19 is an enlarged view of the indicated area of detail shown in FIG. 18, including the trocar assembly and the retaining mechanism shown in FIG. 18;

FIG. 20 is a side perspective view of the trocar assembly and the retaining mechanism shown in FIG. 18, with components of the retaining mechanism separated;

FIG. 21 is an enlarged view of the indicated area of detail shown in FIG. 20;

FIG. 22 is a perspective view of a proximal end of the trocar assembly shown in FIGS. 18-20;

FIG. 23 is a cross-sectional end view of the trocar assembly shown in FIGS. 18-20, taken along section line 23-23 shown in FIG. 22;

FIG. 24 is a side perspective view of an insert member of the retaining mechanism shown in FIGS. 18-20;

FIG. 25 is a perspective view of the proximal end of the trocar assembly shown in FIG. 22 and the insert member shown in FIG. 24, with the proximal end of the trocar assembly partially received though the insert member;

FIG. 26 is the end perspective view of the trocar assembly and insert member shown in FIG. 25, with the proximal end of the trocar assembly fully received though the insert member;

FIG. 27 is a cross-sectional end view of the trocar assembly and insert member shown in FIGS. 26 and 27, taken along section line 27-27 shown in FIG. 26, with the trocar assembly in an unlocked orientation;

FIG. 28 is the cross-sectional end view of the trocar assembly and insert member shown in FIG. 27, with the trocar assembly in a locked orientation;

FIG. 29 is a cross-sectional side view of the trocar assembly and insert member shown in FIGS. 26-28, taken along section line 29-29 shown in FIG. 28;

FIG. 30 is a perspective view of an adapter assembly according to still another exemplary embodiment of the disclosure including a trocar assembly secured within the adapter assembly by a retaining mechanism;

FIG. 31 is an enlarged perspective view of the trocar assembly and the retaining mechanism shown in FIG. 30;

FIG. 32 is a perspective view of the trocar assembly and the retaining mechanism shown in FIGS. 30-32, with parts separated;

FIG. 33 is an enlarged view of the indicated area of detail shown in FIG. 33;

FIG. 34 is a cross-sectional end view of the trocar assembly and the retaining mechanism shown in FIGS. 30-33, taken along section line 34-34 shown in FIG. 31, with the retaining mechanism in a locked condition;

FIG. 35 is a cross-sectional side view of the trocar assembly and the retaining mechanism shown in FIGS. 30-34, taken along section line 35-35 shown in FIG. 34;

FIG. 36 is the cross-sectional side view of the trocar assembly and the retaining mechanism shown in FIG. 34, with the retaining mechanism in an unlock condition;

FIG. 37 is a cross-sectional side view of the trocar assembly and the retaining mechanism shown in FIGS. 30-34, taken along section line 35-35 shown in FIG. 36;

FIG. 38 is a perspective view of a trocar assembly and a retaining mechanism according to yet another exemplary embodiment of the disclosure;

FIG. 39 is a side perspective view of a proximal end of the trocar assembly and the retaining mechanism shown in FIG. 38, with components of the retaining mechanism separated;

FIG. 40 is a cross-sectional end view of the trocar assembly and the retaining mechanism shown in FIGS. 38 and 39, taken along section line 40-40 shown in FIG. 38, with the retaining mechanism in a locked condition;

FIG. 41 is a cross-sectional view of the trocar assembly and the retaining mechanism shown in FIGS. 38-40, taken along section line 41-41 shown in FIG. 40, with the trocar assembly fully received through the retaining mechanism;

FIG. 42 is the cross-sectional view of the trocar assembly and the retaining mechanism shown in FIG. 41, with the trocar assembly partially received through the retaining mechanism;

FIG. 43 is the cross-sectional end view of the trocar assembly and retaining mechanism shown in FIG. 40, with the retaining mechanism in an unlocked condition;

FIG. 44 is a side perspective view of a distal end of an adapter assembly according still yet another exemplary embodiment of the disclosure;

FIG. 45 is an enlarged view of the distal end of the adapter assembly shown in FIG. 44, with an outer sleeve removed and including a trocar assembly and a retaining mechanism;

FIG. 46 is a perspective view of the trocar assembly and the retaining mechanism shown in FIG. 45, with components of the retaining mechanism separated;

FIG. 47 is a cross-sectional top view of a portion of the adapter assembly including the retaining mechanism, with a proximal portion of the trocar assembly in initial engagement with locking members of the retaining mechanism;

FIG. 48 is the cross-sectional top view of the portion of the adapter assembly including the retaining mechanism shown in FIG. 47, with the proximal portion of the trocar assembly partially received through the retaining mechanism;

FIG. 49 is the cross-sectional top view of the portion of the adapter assembly including the retaining mechanism shown in FIG. 47, with the proximal portion of the trocar assembly fully received through the retaining mechanism;

FIG. 50 is a side perspective sectional view of an adapter assembly according to still yet another exemplary embodiment of the disclosure including a retaining mechanism and a trocar assembly fully received through the retaining mechanism;

FIG. 51 is the side perspective sectional view of the trocar assembly and retaining mechanism shown in FIG. 50, with a housing of the retaining mechanism removed;

FIG. 52 is a side perspective view of the retaining mechanism shown in FIGS. 50 and 51, with components separated, and including a distal end of a drive member;

FIG. 53 is a cross-sectional end view taken along section line 53-53 shown in FIG. 50, with the retaining mechanism in a locked configuration;

FIG. 54 is a cross-sectional side cutaway view of the adapter assembly shown in FIG. 50, taken along section line 54-54 shown in FIG. 50, with the retaining mechanism in the locked configuration;

FIG. 55 is the cross-sectional side cutaway view of the adapter assembly shown in FIG. 54, with the retaining mechanism in a partially locked configuration;

FIG. 56 is the cross-sectional side cutaway view of the adapter assembly shown in FIGS. 54 and 55, with the retaining mechanism in an unlocked configuration;

FIG. 57 is the cross-sectional end view of the adapter assembly shown in FIG. 53, with the retaining mechanism in the unlocked configuration;

FIG. 58 is a perspective top view of an adapter assembly according to still another exemplary embodiment of the disclosure, including a retaining mechanism for releasably receiving a trocar assembly;

FIG. 59 is a perspective side view of the retaining mechanism shown in FIG. 58, with components separated;

FIG. 60 is a cross-sectional side view of the adapter assembly shown in FIG. 58, with the retaining mechanism in a locked configuration;

FIG. 61 is the cross-sectional side view of the adapter assembly shown in FIG. 60, with the retaining mechanism in a partially locked configuration; and

FIG. 62 is the cross-sectional side view of the adapter assembly shown in FIGS. 60 and 61, with the retaining mechanism in an unlocked configuration.

DETAILED DESCRIPTION

Embodiments of the disclosed adapter assembly including a retaining mechanism for securing a removable trocar assembly therein will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. As is common in the art, the term “proximal” refers to that part or component closer to the user or operator, i.e. surgeon or clinician, while the term “distal” refers to that part or component further away from the user.

FIG. 1 illustrates a surgical stapling device 10 including an adapter assembly according to an exemplary embodiment of the disclosure, shown generally as adapter assembly 100. The surgical stapling device 10 further includes a powered handle assembly 20, a loading unit 30, and an anvil assembly 40. The loading unit 30 and anvil assembly 40 together form an end effector 50. Although shown and described with reference to surgical stapling device 10, aspects of the disclosure may be modified for use with manual surgical stapling devices having various configurations, and with powered surgical stapling devices having alternative configurations. For a detailed description of exemplary surgical stapling devices, please refer to U.S. Pat. No. 9,023,014 and U.S. Pat. Appl. Publ. No. 2012/0253329.

FIG. 2 illustrates the adapter assembly 100 including an elongate body having a proximal portion 102 configured for operable connection to the handle assembly 20 (FIG. 1) and a distal portion 104 configured for operable connection to the loading unit 30 (FIG. 1) and to the anvil assembly 40 (FIG. 1). Although shown and described as forming an integral unit, it is envisioned that the proximal and distal portions 102, 104 may be formed as separate units that are releasably securable to one another.

The adapter assembly 100 will only be described to the extent necessary to fully disclose the aspects of the disclosure. For a detailed description of an exemplary adapter assembly, please refer to U.S. Pat. No. 10,226,254 (“the '254 patent).

FIG. 3 illustrates the adapter assembly 100 including an outer sleeve 106, and a connector housing 108 secured to a distal end of the outer sleeve 106. The connector housing 108 is configured to releasably secure an end effector, e.g., the end effector 30 (FIG. 1), to the adapter assembly 100. A drive assembly 110 (FIG. 16) including first and second drive assemblies 112, 114 extends through the outer sleeve 106 of the adapter assembly 100. For a detailed description of the structure and function of an exemplary drive assembly, please refer to the '254 patent.

The adapter assembly 100 further includes a trocar assembly 120, and a retaining mechanism 130 releasably securing the trocar assembly 120 relative to the outer sleeve 106 of the adapter assembly 100. The trocar assembly 120 will only be described to the extent necessary to describe the aspects of the disclosure. For a detailed description of the structure and function of an exemplary trocar assembly, please refer to the '254 patent.

FIG. 3 illustrates the trocar assembly 120 of the adapter assembly 100 (FIG. 2) including a trocar housing 122, a trocar member 124 slidably disposed within the trocar housing 122, and a drive screw 126 operably received within the trocar member 124 for axially moving the trocar member 124 relative to the trocar housing 122. The trocar housing 122 defines first and second locking openings 123 a, 123 b (FIG. 12) for receiving respective free ends 146 a, 146 b of first and second retention members 140 a, 140 b (FIG. 5) of the retaining mechanism 130 of the adapter assembly 100.

FIG. 5 shows the retaining mechanism 130 of the adapter assembly 100 including a housing 132 supported within the outer sleeve 106 (FIG. 4) of the adapter assembly 100, first and second retention members 140 a, 140 b operably supported within the housing 132 and configured for selective receipt within the first and second locking openings 123 a, 123 b in the trocar housing 122 of the trocar assembly 120, and first and second biasing members, e.g., first and second leaf springs 160 a, 160 b, secured to the housing 132 and in operable engagement with the respect first and second retention members 140 a, 140 b.

The housing 132 of the retaining mechanism 130 includes a body portion 134 defining a longitudinal opening 131 for receipt of the trocar assembly 120 and first and second flange portions 136 a, 136 b. The first and second flange portions 136 a, 136 b each define a cylindrical opening 133 a, 133 b in communication with the longitudinal openings 131 in the body portion 134 and a slot 135 a, 135 b extending from the respective first and second cylindrical openings 133 a, 133 b. The first and second cylindrical openings 133 a, 133 b and the first and second slots 135 a, 135 b operably receive the respective first and second retention members 140 a, 140 b. In embodiments, and as shown, the body portion 134 of the housing 132 further defines a pair of openings 137 a, 137 b for receiving respective first and second pins 170 a, 170 b, which secure the respective first and second leaf springs 160 a, 160 b to the housing 132.

FIGS. 6-9 illustrate the first and second retention members 140 a (FIG. 5), 140 b of the retaining mechanism 130 each including body portion 142 a (FIG. 5), 142 b, respectively, and a tab portion 144 a (FIG. 5), 144 b, respectively, extending from the respective body portions 142 a, 142 b. Free ends 146 a (FIG. 5), 146 b of the respective first and second retention members 140 a, 140 b include a first cam surface 148 a (FIG. 13), 148 b, respectively, and a second cam surface 150 a (FIG. 16), 150 b. The first cam surfaces 148 a, 148 b of the respective first and second retention members 140 a, 140 b are configured to facilitate loading of the trocar assembly 120 within the adapter assembly 100 (FIG. 2). More particularly, the first cam surfaces 148 a, 148 b face in a distal direction when secured within the housing 132 of the retaining mechanism 130 and are configured to engage a proximal portion 122 a (FIG. 3) of the trocar housing 122 of the trocar assembly 100 during loading of the trocar assembly 120 within the adapter assembly 100. Engagement of the proximal portion 122 a of the trocar housing 122 with the first cam surfaces 148 a, 148 b causes the respective first and second retention members 140 a, 140 b to move radially outwardly.

The second cam surfaces 150 a, 150 b of the respective first and second retention members 140 a, 140 b are configured to facilitate release of the trocar assembly 120 from within the adapter assembly 100. More particularly, the second cam surfaces 150 a, 150 b face in a circumferential direction and are configured to engage the trocar housing 122 when the trocar assembly 120 is rotated about a longitudinal axis “x” of the distal portion 104 (FIG. 2) of the adapter assembly 100. Engagement of the second cam surfaces 150 a, 150 b with the trocar housing 122 as the trocar assembly 100 is being rotated causes the first and second retention members 140 a, 140 b to move radially outwardly.

FIG. 11 illustrates that the tab portions 144 a, 144 b of the first and second retention members 140 a, 140 b of the retaining mechanism 130 are operably received within the respective first and second slots 135 a, 135 b of the housing 132 of the retaining mechanism 130 while the body portions 142 a, 142 b are operably received within the respective first and second cylindrical openings 133 a, 133 b of the housing 132. Receipt of the tab portions 144 a, 144 b of the respective first and second retention members 140 a, 140 b within the respective first and second slots 135 a, 135 b in the housing 132 rotationally secures the first and second retention members 140 a, 140 b relative to the housing 132. In this manner, the first and second retention members 140 a, 140 b are maintained in a fixed orientation relative to a longitudinal axis “x” of the distal portions 104 of the adapter assembly 100. Alternatively, the body portions 142 a, 142 b of the respective first and second retention members 140 a, 140 b include an oval, rectangular, or other non-circular cross-section that would prevent rotation of the first and second retention members 140 a, 140 b within the housing 132.

The first and second retention members 140 a, 140 b of the retaining mechanism 130 are retained within the respective first and second cylindrical openings 133 a, 133 b in the housing 132 of the retaining mechanism 130 by the first and second leaf springs 160 a (FIG. 10), 160 b (FIG. 5), respectively. As noted above, the first and second leaf springs 160 a, 160 b are secured to the housing by 132 the respective first and second pins 170 a (FIG. 10), 170 b (FIG. 11). Although shown secured to the housing 132 with pins 170 a, 170 b, it is envisioned that the first and second leaf springs 160 a, 160 b may be secured to the housing 132 in any suitable manner, including, for example, by welding, using adhesives, with mechanical and/or chemical fasteners, or via friction fit.

FIG. 13 illustrates the adapter assembly 100 prior to loading of the trocar assembly 120 (FIG. 12) within the distal portions 104 of the adapter assembly 100. In this manner, the first and second retention members 140 a, 140 b of the retaining mechanism 130 are in their first or initial positions, with the free ends 146 a, 146 b, respectively, extending within the longitudinal passage 131 of the housing 132 of the retaining mechanism 130.

FIG. 14 illustrates the trocar assembly 120 in a first rotational orientation relative to a longitudinal axis “x” of the distal portion 104 of the adapter assembly 100 as the trocar assembly 120 is loaded within the distal portion 104 of the adapter assembly 100 and moves through the longitudinal passage 131 in the housing 132 of the retaining mechanism 130, as indicated by arrows “A”. As the trocar assembly 120 is loaded, the leading end 122 a of the trocar housing 122 of the trocar assembly 120 engages the first cam surfaces 148 a, 148 b of the respective first and second retention members 140 a, 140 b. Engagement of the first and second cam surfaces 148 a, 148 b by the proximal portion 122 a of the trocar housing 122 causes the first and second retention members 140 a, 140 b to move radially outward, as indicated by arrows “B”, against the bias of the respective leaf springs 160 a, 160 b.

FIGS. 15 and 16 illustrate the trocar assembly 120 fully received within the distal portion 104 of the adapter assembly 100 with the first and second locking openings 123 a, 123 b in the trocar housing 122 of the trocar assembly 120 aligned with the respective first and second retention members 140 a, 140 b of the retaining mechanism 130. When the trocar assembly 120 is fully received within the distal portion 104 of the adapter assembly 100, the bias of the first and second leaf springs 160 a, 160 b on the respective first and second retention members 140 a, 140 b of the retaining mechanism 130 causes the first and second retention members 140 a, 140 b to move radially inward into the respective first and second locking openings 123 a, 123 b of the trocar housing 122, as indicated by arrows “C”. Receipt of the first and second retention members 140 a, 140 b within the respective first and second locking openings 123 a, 123 b secures the trocar assembly 120 within the adapter assembly 100.

Subsequent to use of the adapter assembly 100, or when otherwise desired to remove the trocar assembly 120 from within the adapter assembly 100, the trocar assembly 120 may be withdrawn from the adapter assembly 100 by rotating the trocar assembly 120 about the longitudinal axis “x” of the distal portion 104 of the adapter assembly 100. More particularly, as shown in FIG. 17, when the trocar assembly 120 is rotated about the longitudinal axis “x”, as indicated by arrows “D”, the trocar housing 122 of the trocar assembly 120 engages the second cam surfaces 150 a, 150 b of the respective first and second retention members 140 a, 140 b of the retaining mechanism 130. Engagement of the second cam surfaces 150 a, 150 b of the respective first and second retention members 140 a, 140 b causes the first and second retention members 140 a, 140 b to move radially outward, against the bias of the respective first and second leaf springs 160 a, 160 b, as indicated by arrows “E”. It is envisioned that the trocar assembly 130 may include a feature (not shown) for engagement by a clinician or other personnel, directly, and/or with the assistance of a removal tool (not shown) for facilitating rotation of the trocar assembly 130 about the longitudinal axis “x”, and/or for facilitating withdrawal of the trocar assembly 130 from within the distal portion1 104 of the adapter assembly 100.

Once the first and second retention members 140 a, 140 b of the retaining mechanism 130 are completely withdrawn from within the respective first and second locking openings 123 a, 123 b in the trocar housing 122 of the trocar assembly 120, the trocar assembly 120 may be removed from within the distal portion 104 of the adapter assembly 100.

FIGS. 18-29 illustrate an adapter assembly 200 including a retaining mechanism 230 according to another exemplary aspect of the disclosure for releasably securing a trocar assembly 220 within a distal portion 204 of the adapter assembly 200. The adapter assembly 200 is substantially similar to the adapter assembly 100 described hereinabove, and will only be described in detail as relates to the differences.

FIGS. 18-23 illustrate the trocar assembly 220 including a trocar housing 222, a trocar member 224 slidably disposed within the trocar housing 222, and a drive screw 226 (FIG. 21) operably received within the trocar member 224 for axially moving the trocar member 224 relative to the trocar housing 222. A proximal portion 222 a of the trocar housing 222 defines a semi-annular groove 227, and includes first, second, and third flat section 228 a, 228 b, 228 c (collectively, a plurality of flat sections 228) formed proximal of the semi-annular groove 227. The first, second, and third flat section 228 a, 228 b, 228 c are spaced bout the outer surface of the proximal portion 222 a of the trocar housing 222. The semi-annular groove 227 and the plurality of flat sections 228 of the trocar housing 222 are configured for releasable engagement of the trocar assembly 220 within an insert member 240 of the retaining mechanism 230.

FIG. 20 illustrates the retaining mechanism 230 of the adapter assembly 200 including a yoke or housing 232 and the insert member 240. The housing 232 includes a substantially rectangular body 234 defining a longitudinal passage 231 for receiving the proximal portion 222 a of the trocar housing 222 of the trocar assembly 220, and a cutout 233 in communication with the longitudinal passage 231 for receiving the insert member 240.

FIG. 24 illustrates the insert member 240 of the retaining mechanism 240. The insert member 240 includes a substantially D-shaped body 242 configured to be received within the cutout 233 in the trocar housing 222 of the trocar assembly 230. The insert member 240 defines an opening 241 for receipt of the proximal portion 222 a of the trocar housing 222 of the trocar assembly 220. The insert member 240 includes first, second, and third flat sections 248 a, 248 b, 248 c (collectively, a plurality of flat sections 248). The plurality of flat sections 228 of the trocar housing 222 correspond with the plurality of flat sections 248 of the insert member 240. More particularly, the first flat section 248 a of the insert member 240 corresponds with the first flat section 228 a of the trocar housing 222, the second flat section 248 b of the insert member 240 corresponds with the second flat section 228 b of the trocar housing 222, and the third flat section 248 c of the insert member 240 corresponds with the third flat section 228 c of the trocar housing 222.

FIGS. 25-27 illustrate the trocar assembly 220 in the first rotational orientation relative to the insert member 240. In the first rotational orientation, the plurality of flat sections 228 of the trocar housing 222 of the trocar assembly 220 align with the plurality of flat sections 248 of the insert member 240 of the retaining assembly 230 such that the trocar assembly 220 may be fully received through the opening 241 in the insert member 240.

FIG. 26 shows the trocar assembly 220 fully received through the opening 241 in the insert member 240, e.g., the semi-annular groove 227 in the trocar housing 222 of the trocar assembly 220 aligns with the insert member 240. In this manner, the trocar assembly 130 is able to be rotated about a longitudinal axis “x” of the distal portion 204 of the adapter assembly 200.

FIGS. 28 and 29 illustrate the trocar assembly 220 in a second rotational orientation relative to the insert member 240 of the retaining assembly 230. More, particularly, the trocar assembly 220 has been rotated about the longitudinal axis “x” relative to the insert member 240 in a first direction, as indicated by arrow “F” in FIG. 28, to secure the trocar assembly 130 within the adapter assembly 200. In one aspect of the disclosure, the trocar assembly 220 is rotated ninety degrees (90°) about the longitudinal axis “x”, between the first rotational orientation and the second rotational orientation.

In the second rotational orientation, the proximal portion 222 a of the trocar housing 222 engages the insert member 240 of the retaining assembly 230 to secure the trocar assembly 230 within the distal portion 204 of the adapter assembly 200.

Following use of the adapter assembly 200, the trocar assembly 220 may be rotated about the longitudinal axis “x” in a second direction to cause the release of the trocar assembly 220 from the distal portion 204 of the adapter assembly 200.

FIGS. 30-37 illustrate an adapter assembly 300 according to another aspect of the disclosure. The adapter assembly 300 includes an outer sleeve 306, a retaining mechanism 330 according to another exemplary aspect of the disclosure disposed within a distal portion 304 of an elongate body of the adapter assembly 300, and a trocar assembly 320 releasably securable within the distal portion 304 of the adapter assembly 300.

FIGS. 32-34 illustrate first and second cutouts 323 a, 323 b (FIG. 34) in a trocar housing 322 of the trocar assembly 320. The first and second cutouts 323 a, 323 b in the trocar housing 322 are configured to receive locking portions 338 a, 338 b, respectively, of respective first and second arms 336 a, 336 b of the retainer mechanism 330. The first and second cutouts 323 a, 323 b (FIG. 34) in the trocar housing 322 are at least partially defined by cam surfaces 328 a, 328 b.

The retaining mechanism 330 includes a housing 332 having a substantially rectangular body 334 defining a longitudinal passage 331 for receiving the proximal portion 322 a of the trocar housing 322 of the trocar assembly 320. The first and second arms 336 a, 336 b extend from the body 334 of the housing 332 of the retaining mechanism 330 and are cantilevered to an initial or lock position. The lock portions 338 a, 338 b are disposed on free ends of the first and second arms 336 a, 336 b. The lock portions 338 a, 338 b may include contoured and/or angled leading edges configured to engage the trocar housing 322 during receipt of the trocar assembly 320 into the distal portion 304 of the adapter assembly 300 to facilitate outward flexing of the first and second arms 336 a, 336 b and receipt of the trocar housing 322 within the longitudinal passage 331 of the retaining mechanism 330.

FIGS. 34 and 35 illustrate the trocar assembly 320 fully received within the distal portion 304 of the adapter assembly 300 in a first rotational orientation relative to the longitudinal axis “x” of the distal portion 304 of the adapter assembly 300, and the retaining mechanism 330 of the adapter assembly 300 in a locked configuration. When the trocar assembly 320 is fully received within the distal portion 304 of the adapter assembly 300 and the retaining mechanism 330 is in the locked configuration, the lock portions 338 a, 338 b of the respective first and second arms 336 a, 336 b of the retaining mechanism 330 are received within respective first and second cutouts 323 a, 323 b in the trocar housing 322 of the trocar assembly 320. Receipt of the lock portions 348 a, 348 b of the respective first and second arms 346 a, 346 b within the respective first and second cutouts 323 a, 323 b secures the trocar assembly 320 within the adapter assembly 300.

FIGS. 36 and 37 illustrate the trocar assembly 320 in a second rotational orientation relative to the longitudinal axis “x” of the distal portion 304 of the adapter assembly 300, and the retaining mechanism 330 in a release configuration. In the release configuration, the lock portions 338 a, 338 b of first and second arms 346 a, 346 b of the retaining mechanism 330 are moved radially outward, as indicated by arrows “G”, from within the respective first and second cutouts 323 a, 323 b in the trocar housing 322 of the trocar assembly 320. The lock portions 338 a, 338 b of first and second arms 346 a, 346 b move radially outward when the cam surfaces 328 a, 328 b defining the respective first and second cutouts 323 a, 323 b engage the locking portions 338 a, 338 b of the respective first and second arms 336 a, 336 b as the trocar assembly 320 is rotated about the longitudinal axis “x” of the distal portion 304 of the adapter assembly 300 to the second rotational orientation, as indicated by arrows “H” in FIG. 37.

Radial outward movement of the locking portions 338 a, 338 b of the first and second arms 336 a, 336 b, respectively, of the retaining mechanism 330 caused by the rotational movement of the trocar assembly 320 move the locking portions 338 a, 338 b from within the respective first and second cutouts 323 a, 323 b in the trocar housing 320 of the trocar assembly 320 such that the locking portions 338 a, 338 b no longer engage the trocar housing 322. Disengagement of the locking portions 338 a, 338 b from the trocar housing 322 releases the trocar assembly 320 and permits removal of the trocar assembly 320 from within the distal portion 304 of the adapter assembly 300, as indicated by arrows “I” in FIG. 37.

FIGS. 38-43 illustrate yet another exemplary aspect of the disclosure shown generally as retaining mechanism 430. The retaining mechanism 430 is substantially similar to retaining mechanism 130 described hereinabove, and will only be described in detail as relates to the differences therebetween. The retaining mechanism 430 is configured to releasably secure a trocar assembly 420 within an adapter assembly (not shown). A trocar housing 422 of the trocar assembly 420 defines first and second cutouts 423 a, 423 b (FIG. 40). The first and second cutouts 423 a, 423 b in the trocar housing 422 are at least partially defined by cam surfaces 428 a, 428 b.

FIG. 39 illustrates the retaining mechanism 430 including a housing 432 having a body portion 434 defining a longitudinal opening 431 for receipt of the trocar assembly 420 and first and second cylindrical opening 433 a, 433 b in communication with the longitudinal opening 431 in the body portion 434. The first and second cylindrical openings 433 a, 433 b operably receive the respective first and second retention members 440 a, 440 b of the retaining mechanism 430.

The first and second retention members 440 a, 440 b of the retaining mechanism 430 each include body 442 a, 442 b, respectively, having a first end portion defining a recess 443 a, 443 b for receiving a biasing member, e.g., compression springs 450 a, 450 b, respectively, and a cross opening 445 a, 445 b, respectively, for receiving a retaining pin 460 a, 460 b configured to prevent the respective first and second retention members 440 a, 440 b from passing entirely through the respective first and second cylindrical openings 433 a, 433 b. Alternatively, the first and second retention members 440 a, 440 b may include an annular ridge or tabs about an outer surface of the body 442 a, 442 b, respectively, for maintaining the respective first and second retention members 440 a, 440 b within first and second cylindrical openings 433 a, 433 b, respectively, of the body portion 434 of the housing 432 of the retaining mechanism 430. An outer sleeve 406 (FIG. 40) of the adapter assembly (not shown) maintains the compression springs 450 a, 450 b within the respective recesses 443 a, 443 b of the first and second retention members 440 a, 440 b, respectively.

Free ends 446 a, 446 b of the respective first and second retention members 440 a, 440 b include a cam surface 448 a, 448 b, respectively. The cam surfaces 448 a, 448 b of the respective first and second retention members 440 a, 440 b are configured to facilitate loading of the trocar assembly 420 within the adapter assembly (not shown). More particularly, the cam surfaces 448 a, 448 b face in a distal direction when secured within the housing 432 of the retaining mechanism 430 and are configured to engage a proximal portion 422 a of the trocar housing 422 of the trocar assembly 420 during loading of the trocar assembly 420 with the adapter assembly (not shown). Engagement of the proximal portion 422 a of the trocar housing 422 within the cam surfaces 448 a, 448 b causes the respective first and second retention members 440 a, 440 b to move radially outward, as indicated by arrow “M” in FIG. 43.

FIG. 42 illustrates the trocar assembly 420 in a first rotational orientation as the trocar assembly 420 is received through the retaining mechanism 430, as indicated by arrows “J”. More particularly, the proximal portion 422 a of the trocar housing 422 of the trocar assembly 420 engages the first cam surfaces 448 a, 448 b of the respective first and second retention members 440 a, 440 b of the retaining mechanism 420. Engagement of the trocar housing 422 with the first cam surfaces 448 a, 448 b causes the first and second retention members 440 a, 440 b to move radially outward, as indicated by arrows “K”. Radial outward movement of the first and second retention members 440 a, 440 b allows the proximal portion 422 a of the trocar housing 422 of the trocar assembly 420 to be received through the housing 432 of the retaining mechanism 430.

When the first and second retention members 440 a, 440 b of the retaining mechanism 430 align with the first and second cutouts 423 a, 423 b, respectively, in the trocar housing 422 of the trocar assembly 420, the first and second compression springs 450 a, 450 b bias the respective first and second retention members 440 a, 440 b into the first and second cutouts 423 a, 423 b in the trocar housing 422 to secure the trocar assembly 420 within the adapter assembly (not shown). The first and second pins 460 a, 460 b maintain the first and second retention members 440 a, 440 b within the respective first and second cylindrical openings 433 a, 433 b in the housing 432 of the retaining mechanism 430.

FIG. 43 illustrates the trocar assembly 420 in a second rotational orientation relative to the longitudinal axis “x” of the retaining mechanism 430 fully received though retaining mechanism 420 and. Rotation of the trocar assembly 420 to the second rotational orientation, as indicated by arrows “L”, causes the cam surfaces 428 a, 428 b defining the cutouts 423 a, 423 b in the trocar housing 422 of the trocar assembly 420 to engage the free ends 446 a, 446 b of the first and second retention members 440 a, 440 b. Engagement of the cam surfaces 428 a, 428 b of the trocar housing 422 with the respective first and second retention members 440 a, 440 b causes the first and second retention members 440 a, 440 b to move radially outward, as indicated by arrows “M”, to a release position.

When the first and second retention members 440 a, 440 b of the retaining mechanism 430 are in the release position, the trocar assembly 420 may be withdrawn from the longitudinal passage 431 through the housing 432 in the retaining mechanism 430 to permit separation of the trocar assembly 420 from the adapter assembly (not shown).

FIGS. 44-49 illustrate another aspect of an adapter assembly including a trocar assembly 520 and a retaining mechanism 530 according to another exemplary aspect of the disclosure for releasably retaining the trocar assembly 520 within the adapter assembly 500.

FIG. 45 illustrates the retaining mechanism 530 disposed within a distal portion 504 of the elongate body of the adapter assembly 500. A seal member 508 is disposed proximal of the retaining mechanism 530. The seal member 508 is formed of an elastomeric material and is configured to be frictionally engaged by first and second retention members 540 a, 540 b of the retaining mechanism 530 to retain the first and second retention members 540 a, 540 b in a locked position (FIG. 49).

FIG. 46 shows the trocar housing 522 of the trocar assembly 520 defining first and second openings 523 a, 523 b, and the retaining mechanism 530 including a housing 532 and the first and second retention members 540 a, 540 b. The housing 532 of the retaining mechanism 530 defines a longitudinal passage 531 for receipt of a proximal portion 522 a of the trocar housing 522 of the trocar assembly 520, and first and second recesses 533 a, 533 b in fluid communication with the longitudinal passage 531 for operably receiving the respective first and second retention members 540 a, 540 b. The first and second retention members 540 a, 540 b are pivotally secured within the respective first and second recesses 533 a, 533 b of the housing 532 by a pivot pin 550 a, 550 b.

Each of the first and second retention members 540 a, 540 b includes a body 542 a, 542 b, respectively, having a camming surface 544 a, 544 b, respectively, a locking surface 546 a, 546 b, and an engagement surface 548 a, 548 b. The camming surfaces 544 a, 544 b of the respective first and second retention members 540 a, 540 b are configured to be engaged by the proximal portion 522 a of the trocar housing 522 of the trocar assembly 520 during loading of the trocar assembly 520 within the adapter assembly 500, as indicated by arrow “N” in FIGS. 47 and 48, to pivot the first and second retention members 540 a, 540 b from an initial or preloading position to a loading or release position, as indicated by arrows “P” in FIG. 48, to permit receipt of the proximal portion 522 a of the trocar assembly 522 through the housing 532 of the retaining mechanism 530. The locking surfaces 546 a, 546 b of the respective first and second retention members 540 a, 540 b are configured to engage the trocar housing 522 of the trocar assembly 520 when the first and second retention members 540 a, 540 b are in their locked positions (FIG. 49). The engagement surfaces 548 a, 548 b of the respective first and second retention members 540 a, 540 b are configured to frictionally engage the seal member 508 of the adapter assembly 500 to maintain the first and second retention members 540 a, 540 b in their locked positions. The body portions 542 a, 542 b of the respective first and second retention members 540 a, 540 b may be configured to facilitate engagement of the first and second retention members 540 a, 540 b by a user. In certain aspects of the disclosure, and as shown, the body portions 542 a, 542 b of the respective first and second retention members 540 a, 540 b define slots 541 a, 541 b, respectively, configured for engagement by fingernails of a user.

FIG. 49 illustrates the trocar assembly 520 fully received within the distal portion 504 of the adapter assembly 500 and the first and second retention members 540 a, 540 b in the locked position. The first and second retention members 540 a, 540 b move to the locked position by pivoting of the first and second retention members 540 a, 540 b radially inwardly, as indicated by arrows “Q”. As the first and second retention members 540 a, 540 b pivot to the locked position, the locking surfaces 546 a, 546 b of the respective first and second retention members 540 a, 540 b engage the trocar housing 522 to secure the trocar assembly 520 within the adapter assembly 500.

Removal the trocar assembly 520 from within the adapter assembly 500 includes pivoting the first and second retention members 540 a, 540 b of the retaining mechanism 540 radially outward to disengage the locking surfaces 546 a, 546 b of the respective first and second retention members 540 a, 540 b from the trocar housing 522 of the trocar assembly 520. It is envisioned that the first and second retention members 540 a, 540 b may be moved to the release position directly through engagement by a user, and/or with the assistance of a removal tool (not shown). In some aspects, the retaining mechanism 530 may include biasing members (not shown) for biasing the first and second retention members 540 a, 540 b to the locked position.

FIGS. 50-57 illustrate yet another adapter assembly 600 including a trocar assembly 620, and a retaining mechanism 630 according to another exemplary aspect of the disclosure releasably securing the trocar assembly 620 relative to an outer sleeve (not shown) of the adapter assembly 600.

The trocar assembly 620 of the adapter assembly 600 includes a trocar housing 622 defining first and second locking openings 623 a, 623 b (FIG. 53) for receiving respective first and second retainer members 680 a, 680 b of the retaining mechanism 630 of the adapter assembly 600. The retaining mechanism 630 includes a retaining block 640, a cam wire 650 supported by the retaining block 640, a retaining block extension 660 for maintaining the cam wire 650 relative to the retaining block 640, a button member 670 in operable engagement with the cam wire 650 and pivotally supported relative to the retaining block 640, and first and second retainer members 680 a, 680 b (FIG. 52) supported by the cam wire 650 within the retaining block 640. A torsion spring 690 biases the button member 670 to a first, locked position (FIG. 54).

A first drive member 610 a of a first drive assembly 610 extends through the retaining mechanism 630 of the adapter assembly 600 through the cam wire 650 and between the retaining block 640 and the retaining block extension 660. The first drive member 610 a includes a stop feature 614 and defines a cutout 611 configured to accommodate pivoting of the button member 670. During operation of the adapter assembly 600, the first drive member 610 a is moveable from a first, distal position (FIG. 54) to subsequent proximal positions (FIGS. 55 and 56) to cause the movement of the button member 670 from the locked position (FIG. 54), to a partially locked position (FIG. 55), to a release position (FIG. 56).

FIG. 52 illustrates the retaining block 640 of the retaining mechanism 630 defining a longitudinal passage 641 for receiving the trocar assembly 620 (FIG. 53), first and second opposed cylindrical openings 643 a, 643 b in communication with the longitudinal passage 641 for receiving the respective first and second retainer members 680 a, 680 b, and a channel or slot 645 extending about a perimeter of the retaining block 640 and through the first and second cylindrical openings 643 a, 643 b in the retaining block 640 for receiving the cam wire 650. The first and second retainer members 680 a, 680 b of the retaining mechanism 630 are supported within the first and second cylindrical openings 643 a, 643 b of the retaining block 640 by the cam wire 650 and are configured to be received within first and second locking openings 623 a, 623 b (FIG. 53) of the trocar housing 622 of the trocar assembly 620 when the trocar assembly 620 is fully received within the distal portion 604 of the adapter assembly 600.

The cam wire 650 of the retaining mechanism 630 includes a substantially U-shaped member having a backspan 652, and first and second legs 654 a, 654 b extending from the backspan 652. The backspan 652 includes a button engagement portion 652 a and a pair of shoulders portions 652 b on either side of the button engagement portion 652 a. Each of the first and second legs 654 a, 654 b includes an opposed angled section 656 a, 656 b. The cam wire 650 is received within the channel 645 of the retaining block 640. The cam wire 650 is moveable between a lock position (FIG. 53) when the button member 870 is in the locked position, and a release position when the button member 670 is pivoted through the partially locked position (FIG. 54) to the release position (FIG. 55).

The retaining block extension 660 includes a frame 662 defining an opening 661 and having a pair of pivot members 664 extending within the opening 661. The button member 670 is pivotally supported within the opening 661 in the frame 662 by the pivot members 664.

The button member 670 of the retaining mechanism 630 includes a body portion 672 having a first engagement surface 672 a, and a second engagement surface 672 b, each of which is configured for operable engagement by a user. A flange 674 extends from the body portion 672 of the button member 670 and is configured to engage the stop feature 614 on the first drive member 610 a of the first drive assembly 610 when the first drive member 610 a is in the distal position. The body portion 672 of the button member 670 defines a cylindrical opening 671 for receiving the pivot members 664 of the retaining block extension 660, and a slot 673 for receiving a portion of the torsion spring 690.

The first engagement surface 672 a of the body portion 672 of the button member 670 of the retaining mechanism 630 is configured to engage the engagement portion 652 a of the backspan 652 of the cam wire 650.

The first and second retention members 680 a, 680 b of the retaining mechanism 630 form substantially cylindrical bodies 682 a, 682 b and are supported on the angled portions 656 a, 656 b of the respective first and second legs 654 a, 654 b of the cam wire 650. The first and second retention members 680 a, 680 b may include tapered inner surfaces 682 a, 682 b to facilitate receipt of the trocar assembly 620 through the retaining block 640 of the retaining mechanism 630.

The first and second retention members 680 a, 680 b each define a stepped opening 681 a, 681 b through which the respective angled portion 656 a, 656 b of the cam wire 650 is received. The cam wire 650 and the stepped openings 681 a, 681 b of the respective first and second retention members 680 a, 680 b are configured such that when the cam wire 650 is in the first position, the first and second retention members 680 a, 680 b extend from within the retaining block 640 into the longitudinal passage 641. In this manner, when a trocar assembly 620 is fully received within the distal portion 604 of the adapter assembly 600, the first and second retention members 680 a, 680 b are received within the respective first and second locking openings 623 a, 623 b of the trocar housing 622 of the trocar assembly 620. Conversely, when the cam wire 650 is in the second or release position, the first and second retention members 680 a, 680 b are retracted from within the longitudinal passage 641 of the retaining block 640 to permit insertion and/or removal of the trocar assembly 620 from the distal portion 604 of the adapter assembly 600.

FIGS. 53 and 54 illustrate the retaining mechanism 630 of the adapter assembly 600 with the cam wire 650 in the lock position, and the button member 670 in the locked position. The trocar assembly 620 is securely received within the distal portion 604 of the adapter assembly 600. The cam wire 650 of the retaining mechanism 630 is secured in the lock position by the flange 674 of the button member 670.

FIG. 55 illustrates the button member 670 of the retaining mechanism 630 in the partially locked position. Proximal movement of the first drive member 610 a of the first drive assembly 610, as indicated by arrow “R”, engages the stop feature 614 of the first drive member 610 a with the body portion 672 of the button member 670 to cause pivoting of the of the button member 670 in a first direction, as indicated by arrow “S”. Pivoting of the button member 670 to the partially locked position exposes the second engagement surface 672 b of the button member 670 to permit engagement of the second engagement surface 672 b by the user.

FIGS. 56 and 57 illustrate the button member 670 of the retaining assembly 630 in the release position. To move the button member 670 to the release position, the user (not shown) continues to pivot the button member 670 in the first direction, as indicated by arrow “S”, to cause the first engagement surface 672 a of the button member 670 to engage the engagement portion 652 of the cam wire 650. Engagement of the cam wire 650 by the button member 670 causes the cam wire 650 to move to the release position, as indicated by arrows “T” in FIG. 57. Movement of the cam wire 650 to the release position causes the first and second retention members 680 a, 680 b to move radially outward, out of engagement with the trocar housing 622 of the trocar assembly 620.

Once the first and second retention members 680 a, 680 b of the retaining mechanism 630 are disengaged from the trocar housing 622 of the trocar assembly 620, the trocar assembly 620 may be removed from within the distal portion 604 of the adapter assembly 600.

FIGS. 58-62 illustrate an adapter assembly 700 including a retaining mechanism 730 according to still yet another aspect of the disclosure for releasably securing a trocar assembly 730 within a distal portion 704 of the adapter assembly 700. The retaining mechanism 730 is substantially similar to the retaining mechanism 530 described hereinabove, and will only be described in detail as relates to the differences therebetween.

FIG. 59 shows the retaining mechanism 730 including a housing 732 supporting first and second retention members 740 a, 740 b. The first and second retention members 740 a, 740 b are pivotally supported by pivot pins 750 a, 750 b, respectively, and are pivotable between a locked position (FIG. 60), a partially released position (FIG. 61), and a release position (FIG. 62).

The first and second retention members 740 a, 740 b each include a handle portion 742 a, 742 b and a locking portion 744 a, 744 b. The handle portions 742 a, 742 b of the respective first and second retention members 740 a, 740 b are configured for operable engagement by a user. Free ends 746 a, 746 b of the respective handle portions 742 a, 742 b are positioned and configured to frictionally engage a seal member 708 of the adapter assembly 700 to maintain the respective first and second retention members 740 a, 740 b in a locked position.

FIG. 60 illustrates the first and second retention members 740 a, 740 b in the locked position. In the locked position, the locking portion 744 a, 744 b of the respective first and second retention members 740 a, 740 b of the retaining mechanism 730 are received within first and second openings 723 a, 723 b of a trocar housing 722 of the trocar assembly 720. In the locked position, the handle portions 742 a, 742 b of the respective first and second retention members 740 a, 740 b frictionally engage the seal member 708 of the adapter assembly 700 to [maintain the respective first and second retention members 740 a, 740 b in the locked position.

FIG. 61 shows proximal movement of the trocar assembly 730 as indicated by the arrow “U”. During proximal movement of the trocar assembly 730, engagement of the trocar housing 722 of the trocar assembly 720 with the locking portions 744 a, 744 b of the respective first and second retention members 740 a, 740 b causes the first and second retention members 740 a, 740 b to pivot to the partially locked position. In the partially locked position, the handle portions 742 a, 742 b of the respective first and second retention members 740 a, 740 b are engageable by a user to continue pivoting the first and second retention members 740 a, 740 b to the release position.

FIG. 62 illustrates the first and second retention members 740 a, 740 b of the retaining mechanism 730 in the release position. When in the release position, the locking portions 744 a, 744 b of the respective first and second retention members 740 a, 740 b are completely retracted from within the first and second openings 723 a, 723 b, respectively, in the trocar housing 722 of the trocar assembly 720. In this manner, the trocar assembly 720 may be removed from within the distal portion 704 of the adapter assembly 700.

Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary aspects of the disclosure. It is envisioned that the elements and features illustrated or described in connection with one exemplary aspect may be combined with the elements and features of another without departing from the scope of the disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described aspects. Accordingly, the disclosure is not to be limited by what has been particularly shown and described. 

What is claimed is:
 1. An adapter assembly for connecting a loading unit to a handle assembly, the adapter assembly comprising: an elongate body having a proximal portion and a distal portion, the proximal portion being configured for operable engagement with an actuation assembly and the distal portion defining a longitudinal axis and being configured to operably receive a trocar assembly; and a retaining mechanism configured to releasably secure the trocar assembly within the distal portion of the elongate body, the retaining mechanism including: a housing; and first and second flexible arms extending from the housing, the first and second flexible arms each including: a free end; and a locking portion disposed on the free end, the locking portions of the first and second flexible arms are positioned to be received within first and second cutouts of a trocar housing of the trocar assembly when the trocar assembly is received within the distal portion of the elongate body and in a first rotational orientation relative to the longitudinal axis, and the locking portions of the first and second flexible arms are flexed radially outward from the respective first and second cutouts when the trocar assembly is in a second rotational orientation relative to the longitudinal axis.
 2. The adapter assembly of claim 1, wherein the first and second flexible arms are in a locked position when the trocar assembly is received within the distal portion of the elongate body in the first rotational orientation relative to the longitudinal axis, and the first and second flexible arms are in a release position when the trocar assembly is received within the distal portion of the elongate body in the second rotational orientation relative to the longitudinal axis.
 3. The adapter assembly of claim 2, wherein rotation of the trocar housing of the trocar assembly about the longitudinal axis from the first rotational orientation to the second rotational orientation flexes the first and second flexible arms radially outward.
 4. The adapter assembly of claim 2, wherein the trocar housing of the trocar assembly is rotated in a first direction about the longitudinal axis from the first rotational orientation to the second rotational orientation.
 5. The adapter assembly of claim 4, wherein the first direction is counterclockwise about the longitudinal axis.
 6. The adapter assembly of claim 1, wherein the lock portion of the first flexible arm is disposed opposite the lock portion of the second flexible arm.
 7. The adapter assembly of claim 1, wherein the housing defines a longitudinal passage for receiving the trocar housing of the trocar assembly.
 8. The adapter assembly of claim 1, further including a trocar assembly releasably securable within the distal portion of the elongate body, the trocar assembly including a trocar housing defining first and second cutouts.
 9. The adapter assembly of claim 8, wherein the trocar housing includes first and second camming surfaces defining the respective first and second cutouts.
 10. The adapter assembly of claim 9, wherein the first and second camming surfaces are configured to flex the respective first and second flexible arms radially outward when the trocar assembly is rotated about the longitudinal axis from the first rotational orientation relative to the longitudinal axis to the second rotational orientation relative to the longitudinal axis.
 11. The adapter assembly of claim 1, wherein the housing and the first and second flexible arms are integrally formed.
 12. A surgical stapling device comprising: an actuation assembly; an adapter assembly including an elongate body having a proximal portion and a distal portion, the proximal portion in operable engagement with the actuation assembly; a trocar assembly releasably securable within the distal portion of the adapter assembly, the trocar assembly including a trocar housing defining first and second cutouts; and a retaining mechanism configured to releasably secure the trocar assembly within the distal portion of the elongate body, the retaining mechanism including: a housing; and first and second flexible arms extending from the housing, the first and second flexible arms each including: a free end; and a locking portion disposed on the free end, the locking portions of the first and second flexible arms are positioned to be received within the respective first and second cutouts in the trocar housing of the trocar assembly when the trocar assembly is received within the distal portion of the elongate body in a first rotational orientation relative to the longitudinal axis, and the locking portions of the first and second flexible arms are flexed radially outward from the respective first and second cutouts when the trocar assembly is received within the distal portion of the elongate body in a second rotational orientation relative to the longitudinal axis.
 13. The surgical stapling device of claim 12, wherein the first and second flexible arms are in a locked position when the trocar assembly is received within the distal portion of the elongate body in the first rotational orientation relative to the longitudinal axis, and the first and second flexible arms are in a release position when the trocar assembly is received within the distal portion of the elongate body in the second rotational orientation relative to the longitudinal axis.
 14. The surgical stapling device of claim 13, wherein rotation of the trocar housing of the trocar assembly about the longitudinal axis from the first rotational orientation to the second rotational orientation flexes the first and second flexible arms radially outward.
 15. The surgical stapling device of claim 13, wherein the trocar housing of the trocar assembly is rotated in a first direction about the longitudinal axis from the first rotational orientation to the second rotational orientation.
 16. The surgical stapling device of claim 15, wherein the first direction is counterclockwise about the longitudinal axis.
 17. The surgical stapling device of claim 12, wherein the lock portion of the first flexible arm is disposed opposite the lock portion of the second flexible arm.
 18. The surgical stapling device of claim 12, wherein the housing defines a longitudinal passage for receiving the trocar housing of the trocar assembly. 